(a) Field of the Invention
The present invention relates to a semiconductor device and a method of manufacturing the same, and more particularly to a method of manufacturing silicide used to reduce a contact resistance at a contact of a semiconductor device and a semiconductor device with the silicide manufactured by the same method.
(b) Description of the Related Art
In general, a semiconductor device includes a plurality of transistors, each of which includes a source/drain electrode and a gate electrode in each of device regions separated from one another by a device isolation method such as a LOCOS (local oxidation of silicon) or STI (shallow trench isolation) method, and titanium silicide or cobalt silicide used to reduce a contact resistance of a transistor driving circuit.
Techniques related to the silicide formation process are disclosed in U.S. Pat. Nos. 6,534,390, 6,316,362, 6,013,566, 5,869,397, and 5,780,350
Hereinafter, a method of manufacturing the silicide according to the prior art is in brief described with reference to FIG. 3 as follows.
First, as shown in FIG. 3A, a transistor 104 including a source/drain electrode 104a and a gate electrode 104b is formed between two device isolation regions 102 of a semiconductor substrate 100, and then a cleaning process for removing a variety of undesired impurities such as metal impurities, organic contaminations or natural oxide films residual on the semiconductor substrate 100 is performed.
Here, a chemical cleaning process to use SC1 (standard cleaning: an organic mixture where NH4OH:H2O2:H2O is 1:4:20) solution and HF or DHF (dilute HF) solution is used as the cleaning process.
Next, as shown in FIG. 3B, a metal film 106 is formed by sputtering metal, such as cobalt for forming silicide in a sputter chamber in a sputter system, on the entire surface of the semiconductor substrate 100. At this time, the semiconductor substrate 100 is heated at a temperature of 20-50° C. After forming the metal film 106, a Ti or TiN protection film 108 for preventing nitrification or contamination of the metal film 106 in the course of a post-heat treatment process is deposited.
Next, as shown in FIGS. 3C and 3D, silicide 110 is formed by picking and placing the semiconductor substrate 100 into a RTP (rapid thermal process) equipment or an electric furnace and then post-heat treating it at a temperature of 400-600° C. Subsequently, after removing residual metal film 106 not used for the formation of the silicide 100, silicide 110 with a low resistance is completed by annealing the semiconductor substrate 100 and stabilizing a phase of the silicide 100.
However, in the prior art as described above, since the silicide 110 is formed through the post-heat treatment process, and the protection film 108 for protecting a surface of the metal film 106 at the time of the formation of the silicide 110 has to be formed, there is a problem of increase of process time.